2025 年 42 巻 3 号 p. 389-393
Autoimmune cerebellar ataxia is classified into several subtypes, including gluten ataxia, anti–glutamate decarboxylase (GAD) ataxia, paraneoplastic cerebellar degeneration (PCD), primary autoimmune cerebellar ataxia, and postinfectious cerebellar ataxia. The effectiveness of a strict gluten–free diet and intravenous immunoglobulin (IVIg) therapy has been reported for gluten ataxia. The treatment of the underlying neoplasm, including tumor resection, chemotherapy and ICI, is mandatory for PCD. In addition, IVIg, PE, steroids, immunosuppressants, and rituximab can also be considered as alternative treatment options for PCD. Therapy of primary autoimmune cerebellar ataxia associated with antibodies against autoimmune cerebellar ataxia to cell surface neuronal antigens, including mGluR1 antibody, comprise IVIg, PE, steroids, immunosuppressants, and rituximab. In patients with PCD–LEMS, the treatment of the neoplasms improves their symptoms. Recently, cerebellar involvement associated with immune–related adverse events (irAEs) has been reported. The discontinuation of immune checkpoint inhibitors, steroids, and/or IVIg is used to treat cerebellar irAEs in severe cases.